[Qemu-devel] [PATCH 01/47] rules.mak: New logical functions

[Ákos Kovács]

lnot, land, lor, lif, eq, ne, isempty, notempty functions added
Example usage:
    obj-$(call lor,$(CONFIG_LINUX),$(CONFIG_BSD)) += feature.o

Signed-off-by: Ákos Kovács <address@hidden>
---
 rules.mak |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/rules.mak b/rules.mak
index 4499745..7e8e3bd 100644
--- a/rules.mak
+++ b/rules.mak
@@ -106,6 +106,22 @@ clean: clean-timestamp
 obj := .
 old-nested-dirs :=
 
+# Logical functions
+lnot = $(if $(subst n,,$1),n,y)
+
+land-yy = y
+land = $(land-$1$2)
+
+lor = $(if $(subst $2,,$1)$(subst $1,,$2),n,y)
+
+lif = $(if $(subst n,,$1),$2,$3)
+
+eq = $(if $(subst $2,,$1)$(subst $1,,$2),n,y)
+ne = $(if $(subst $2,,$1)$(subst $1,,$2),y,n)
+
+isempty = $(call eq,$1,)
+notempty = $(call ne,$1,)
+
 define push-var
 $(eval save-$2-$1 = $(value $1))
 $(eval $1 :=)
-- 
1.7.10.4